Remove unused EVS functions in qwen3_vl.py

[gty111]

Purpose

In qwen3_vl.py, functions including _get_evs_mask_segments, _extract_frame_offsets_from_mask, and _get_actual_frame_token_counts were introduced in #29752. However, their calls were removed in #33607 while their definitions were left untouched.
This PR removes the unused EVS-related functions from qwen3_vl.py.

Test Plan

Test Result

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[Copilot]

Pull request overview

This PR removes EVS-related helper methods from qwen3_vl.py that were introduced earlier but no longer have any call sites after subsequent refactors, reducing dead code in the Qwen3-VL model implementation.

Changes:

• Removed _get_evs_mask_segments, _extract_frame_offsets_from_mask, and _get_actual_frame_token_counts from Qwen3VLForConditionalGeneration.
• Kept existing EVS-aware logic that now relies on token markers (vision_start_token_id / vision_end_token_id) for frame iteration.

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[gemini-code-assist]

Code Review

This pull request removes three unused EVS-related functions (_get_evs_mask_segments, _extract_frame_offsets_from_mask, and _get_actual_frame_token_counts) from vllm/model_executor/models/qwen3_vl.py. This change cleans up dead code, which improves the maintainability of the codebase. I have confirmed that these functions are not called within the provided context. The change is correct and I have no further comments.

[Isotr0py]

Thanks for cleanup!